Pubs in the city of Bath serve the least clean beer in the UK, while the South West is the worst region for unclean beer lines (with 40% of lines unclean).
Meanwhile, Newcastle and Warrington are where the cleanest beer can be found, with the North East the cleanest region with only 27% of beer lines adjudged to be unclean.
That's according to the Beer Quality Report 2017, which was launched this morning by internet of things provider Vianet, which monitors the flow of beer through lines in pubs across the country, and beer quality accreditation and training firm Cask Marque.
The report found a clear north-south divide when it comes to beer quality, with the proportion of beer going through unclean lines in some parts of the country markedly higher than in others. Pubs and other establishments serving beer and cider should generally clean their lines on a seven-day cycle or risk a deterioration quality and a fall-off in demand from customers.
Cleaning lines regularly to ensure a higher quality of beer was just one of the measures outlined by Vianet and Cask Marque that could to help pubs save significant sums of money at a time when operating costs are set to rise - pushed upwards by the factors including the National Living Wage, the Apprenticeship Levy, and business rates.
The report said that the pub industry as a whole was losing £709m a year due to problems with beer quality, while individual pubs were, on average, missing out on £14,600 - more than enough to offset the £7,178 average annual additional cost per pub created by extra employment regulation and business rates.
Analysis showed that that within that £709m, the pub industry is missing out on:
• an achievable extra £206m in waste reduction at a retail selling price of £3.50 per pint
• a 2% improvement in till yield of £248m
• an additional estimated £182m in potential sales by delivering a consistently great pint, typically through improved line cleaning and serving beer to the customer at the correct temperature and specification.
• Some £73m through the cost of over-ranging and wasted beer taps on the bar
The report takes data from more than 220,000 Vianet devices in pubs and cellars across the country, which is then informed and validated by quality scores from Cask Marque's annual visits to more than 22,000 pubs.
The report found that most retailers had failed to improve beer quality since last year's report, with the same proportion of beer served too warm. Meanwhile, one in three pints served to a UK consumer is via a line overdue a clean - the same proportion as last year.
The report found that the average annual difference in beer volumes of pubs that serve almost all beer via clean lines (between 90-100% of beer) and those that serve less than half (40-50%) via clean lines, is 63 barrels. That equates to 18,144 pints over the course of a year and is worth approximately £63,500 at a retail selling price of £3.50 a pint. Assuming a gross profit margin of 50%, that's worth £32,000 a year to the operator.
Steve Alton, managing director of Vianet, said: "This report lays bare the profit opportunity for all operators across the pub sector, regardless of whether they run managed, tenanted or independent outlets.
"The message is good operators could have better business by driving up retail standards and, in turn, help safeguard the future of the category and keep pubs attractive to consumers. Draught beer remains in value growth and beer still accounts for about seven in 10 drinks sold in pubs."
Paul Nunny, director of Cask Marque, suggested that the lack of improvement in beer quality since last year's report was down to a lack of training by operators, who were facing a range of cost pressures.
He said: "Cask Marque has spent nearly 20 years banging the drum about beer quality and still the message is not getting through to retailers. This is a damning report on the quality offer to consumers. Findings from our own recent research showed that 49% of pubs are not meeting Cask Marque standards. Thank goodness nearly 10,000 pubs can!"
In other findings, one in four pubs were found to have major temperature issues last year, with 6% of all pints served too warm. Scotland was the region with the highest percentage of beer served too warm, with the West Midlands most likely to keep beer at the right temperature.
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